I have had all those symptoms u had mentioned in my 200TE. My mechanics tried to cure it for about 5 weeks & finally it all boiled down to faulty ECU.
I tried getting one locally (India) and found out the price to around USD1800, tried Srilank ,the price was USD1500 approx.Singapore & Malaysia had no stock,price not given,had to place order.Since I didnt have much time to wait there ,I did not place order with them
Finally I found one used piece with 2 blown capacitors, in Dubai UAE, for an unbeliviable USD 69.Bought it ,changed the capacitors.
Now the car is back on the road.Hope this might be of some academic interest.